Why are apples good for us?
A number of components in apples, most notably fiber and phytonutrients have been found in studies to lower blood cholesterol and improve bowel function, and may be associated with a reduced risk of ischemic heart disease, stroke, prostate cancer, type II diabetes and asthma. Preliminary research from Finland indicates diets with the highest intake of apple phytonutrients were associated with a 46 percent reduction in the incidence of lung cancer. Findings indicate that two apples a day or 12 ounces of 100% apple juice reduced the damaging effects of the "bad" LDL cholesterol.
Dr. Victor Fulgoni analyzed adult food consumption data collected in the 1999-2004 National Health and Nutrition Examination Survey -- the government's largest food consumption and health database.
Adults who eat apples and applesauce and drink apple juice have a significantly reduced risk of metabolic syndrome -- defined as having three or more of the associated symptoms related to cardiovascular risk, including elevated blood pressure, increased waist size and elevated C-reactive protein levels.
The study found those who consumed apple products had a 30 percent decreased likelihood for elevated diastolic blood pressure and a 36 percent decreased likelihood for elevated systolic blood pressure and a 21 percent reduced risk of increased waist circumference.
"We found that adults who eat apples and apple products have smaller waistlines that indicate less abdominal fat, lower blood pressure and a reduced risk for developing what is known as metabolic syndrome," Fulgoni said in a statement.
Additionally, adult apple-product consumers had significantly reduced C-reactive protein levels -- a biomarker of inflammation used to detect increased risk for diabetes, hypertension and cardiovascular disease.
Washington - The apples and apple juice you consume may have positive effects in one of the most unlikely places in the body - in the colon. New research has demonstrated that components in both apple pectin and apple juice actually enhance biological mechanisms that have anticarcinogenic effects in the colon.
Using human fecal matter as the test substance, German researchers Dr. Dieter Schrenk, M.D. and his colleagues hypothesized that the compound butyrate could be increased in the presence of apple pectin and apple juice extracts.
Butyrate has been suggested to be chemopreventative in that it might prevent the occurrence of colorectal cancer, which is very common in Western industrialized countries. It is a short chain fatty acid which is seen as a major contributing factor to a healthy colon. The research notes, "Butyrate not only serves as a major nutrient for the colon epithelia but is also thought to play an important role in the protective effect of natural fiber against colorectal cancer."
So how do apple pectin and apple juice extracts play a role in increasing amounts of butyrate? The laboratory tests performed by Schrenk found that the increased production of butyrate from the addition of apple components inhibited histone deacetlyases (HDAC). A slowed production of HDAC results in significantly less growth of precancerous and tumor cells.
The research, published in the April 2008 issue of Nutrition, notes, "apples are a major source of natural fiber and of low molecular weight plan polyphenols in the Western diet." The researchers conclude, "Pectin-rich apple products can thus be expected to exert anticarginogenic effects in the colon."
Over the past four years, apple consumption has been linked with reduced cancer risk in several studies. A 2001 Mayo Clinic study indicated that quercetin, a flavonoid abundant in apples, helps prevent the growth of prostate cancer cells. A Cornell University study indicated phytochemicals in the skin of an apple inhibited the reproduction of colon cancer cells by 43 percent. The National Cancer Institute has reported that foods containing flavonoids like those found in apples may reduce the risk of lung cancer by as much as 50 percent.
- Carcinogenesis (March, 2001)
- Nature (June, 2000)
- Journal of the National Cancer Institute (January, 2000)
- American Thoracic Society Meeting (May, 2001)
-Thorax (January, 2000)
-The British Medical Journal (1996)
"This new study suggests that eating and drinking apples and apple juice, in conjunction with a balanced diet, can protect the brain from the effects of oxidative stress - and that we should eat such antioxidant-rich foods," notes lead researcher Thomas B. Shea, Ph.D ., director of the University of Massachusetts Lowell's Center for Cellular Neurobiology and Neurodegeneration Research, whose study was just published in the latest issue of the Journal of Alzheimer's Disease. Although more research is needed, Shea is excited about these brain health findings, which are encouraging for all individuals who are interested in staying mentally sharp as they age.
Using a well-established animal protocol, Shea and his research colleagues assessed whether consumption of apple juice was protective against oxidative brain damage in aging mice, damage that can lead to memory loss. "These newer findings show that there is something in apples and apple juice that protects brain cells in normal aging, much like the protection we previously saw against Alzheimer-like symptoms," says Shea.
The researchers evaluated adult and aged mice using a standard diet, a nutrient-deficient diet, and a nutrient-deficient diet supplemented with apple juice concentrate in drinking water. Although the adult mice tested were not affected negatively by the deficient diets, the aged mice were, which is consistent with normal aging due to oxidative neurodegeneration. The effect on cognition among the aged mice was measured through well-established maze tests, followed by an examination of brain tissue. However, the aged mice who consumed the diets supplemented with apple juice performed significantly better on the maze tests and all had less oxidative brain damage than those on the standard diet.
Supplementation by apple juice fully protected the aged mice from the oxidative stress caused by the nutrient-deficient diet. In addition, stronger mental acuity resulted when the aged mice consumed the human equivalent of 2-3 cups of apple juice or approximately 2-4 apples per day. "We believe that this effect is due to the apple's naturally high level of antioxidants," states Shea. Previous research with his colleagues also determined that it is not the sugar and energy content of the apple juice, but the antioxidant attributes of apple juice that are responsible for the positive effects.
This study was sponsored through an unrestricted grant by the U.S. Apple Association and the Apple Products Research and Education Council.
The research abstract can be found at www.j-alz.com/issues/8/vol8-3.html.
-University of Massachusetts Lowell
Women of all ages are encouraged to consume more fruit and vegetables, including apples and apple products, for heart health. However, this study focused on postmenopausal woman, a group becoming more aware of the risk for heart disease. Using a government database that assesses the flavonoid-compound content of foods, the researchers hypothesized that flavonoid intake (in general and from specific foods), might be inversely associated with mortality from CVD and CHD among the women in the study selected for this research analysis were postmenopausal and part of the ongoing Iowa Women's Health Study, each of which has been monitored for dietary intake and various health outcomes for nearly 20 years.
As a result of the extensive analysis that considered what the women ate, the types of cardiovascular-related diseases they experienced, and the overall flavonoid content of an extensive list of foods, the researchers concluded that consumption of apples, pears and red wine were linked with the lowest risk for mortality related to both CHD and CVD (not just one or the other).
"Flavonoids are compounds found in small quantities in numerous plant foods, including fruits and vegetables, tea, wine, nuts and seeds, and herbs and spices," say the university researchers from the University of Minnesota and the University of Oslo (Norway) Earlier research has indicated that flavonoids also have antioxidant properties that are linked to the reduction of oxidation of the bad (LDL - low density lipoprotein) cholesterol which have been linked in various ways with the development of CVD. According to the government database cited in this paper, apples contain a wide variety of flavonoid compounds.
The researchers also believe this is the first prospective study of postmenopausal women to report on the intake and impact of total and specific flavonoid subclasses. They conclude, "Dietary intakes of flavanones, anthocyanins, and certain foods rich in flavonoids were associated with reduced risk of death due to CHD, CVD and all causes."
The publication of this positive study for apples comes on the heels of updated heart disease prevention guidelines for women just released by the American Heart Association in the February 20 issue of Circulation. As part of their guidelines, AHA emphasizes that women increase their intake of fruits and vegetables to help prevent heart disease over their lifetime, not just to reduce short-term risk. Worldwide, cardiovascular disease is the largest single cause of mortality among women, accounting for one third of all deaths.